1. Field of the Invention
This invention relates generally to a power supply system for a personal computer (PC). More particularly, this invention relates to a new approach to design and manufacture the power supply system with a modularized and integrated cable interface for connecting a plurality of output (O/P) cable-groups to several standard output (O/P) cable terminals on a printed circuit board (PCB) in the power supply system for providing power from an external power source for supplying DC power at predefined voltage level to each subsystem of a personal computer via these several O/P cable groups.
2. Description of the Prior Art
The power supply system for a personal computer are required to provide power to increasingly more `peripherals`, such as modem-facsimile, compact disk (C-D) driver, scanners, hard-disk drives, floppy disk drives, etc. Due to current trend of development in personal computers, it can be expected that such trend will continue. Particularly when the microprocessor which is generally referred to as the central processing unit (CPU) are becoming more powerful and capable to manage multimedia, multitask functions. In addition to the this trend, each type and model of personal computers often has unique arrangement and configuration by placing these peripherals in different locations. In order to satisfy the very complicate requirements for providing power to all the peripherals, a power supply system including the power cable and the interface connectors are required to be custom designed to uniquely meet the specifications of each model of computer system design.
FIG. 1 shows a prior art power supply system 10 which includes several output (O/P) cable groups, i.e., cable groups 15-1, 15-2, 15-3, and 15-4 for connecting to the CPU and various different peripherals such as hard-disk derive (HDD), floppy disk drive (FDD), compact disk drive (CDD), modem-facsimile board and monitor. The power supply system also has a power cable 20 for connecting to an external power source connector 25. The external power source connector is typically installed at the back-panel of a personal computer for connecting to an external source via a power line (not shown). Depending on the internal space arrangement, the power supply system 10 for a personal computer can be located at different positions in a personal computer system. The length of the power cable 20 and those of the O/P cable groups 15-1, 15-2, 15-3, and 15-4 are all different. For this reason, the general practice in manufacturing the power supply system for a personal computer is to custom design and then `tailor-make` those cables and group them in accordance with the specifications of each purchase order.
Special notice should also be taken with respect to the welding or soldering of each individual O/P cable to a particular connection point on the printed circuit board (PCB) of the power supply system. Due to this individual cable connection configuration, the conventional manufacture process must handle the length of each O/P cable on an individual basis as each O/P cable may have different length when a particular O/P cable is pre-designated to be welded to a specific connection point on the PCB and to be included in a specific cable group to provide a specific DC voltage for a predetermined peripheral sub-system. Due to this point-to-point design concept, a power supply system, including the design of each O/P cable such as the connection point on the PCB in the power supply system and length of each O/P cable, are specifically designed and manufactured according to customer specifications for each brand-model.
One example of these power supply systems is ASTEC's power supply Model AS145-3420 which has output cable connection and output cable groups as that shown in FIGS. 2A and 2B for an IBM personal computer. FIG. 2A is a side view of a power supply wherein a plurality of output cables from the AS145-3420 power supply is connected directly from the power supply unit near the top of the panel along a surface in the A-A' direction. The output-cable connection 40 of this power supply AS145-3420 unit is the same as that shown in FIG. 1. FIG. 2B shows the detail groupings of these output cables, i.e., cable groups 45-1 to 45-6. Since the groupings of these output cables 45-1 to 45-6 may be different for different model of computers, this Model AS145-3420 power supply shows a typical design approach generally used. It should be noted that in FIG. 2B, each O/P cable is to provide a specific output DC voltage to a particular pin as marked out for each pin. The DC voltages for these pins can be a ground voltage, -5 volts, +5 volts, -12 volts, and +12 volts as shown. A different color is used for each O/P cable for easy recognition of different DC voltage assigned to that O/P cable. Because ASTEC is one of the major power supply companies for the personal computers worldwide while IBM has continuously dominated the PC market share, the design method as shown for ASTEC145-3420 demonstrates the level of ordinary skill in the art of power supply design in the particular field pertinent to the personal computer systems.
Therefore, there is still a need for a new system configuration and design method in the art of power-supply design and manufacture in order to resolve these difficulties and limitations. Specifically, this new system configuration and design approach must be able to provide a more flexible scheme to satisfy different customer's requirements in providing power to many subsystems in a personal computer which may be arranged in many different ways according to the packaging layout, the level of integration, the performance level, the intended computer functions and a wide variety of other design considerations that the computer system designer may take into account.